Not Applicable
Not Applicable
This invention relates to a dispenser packing.
Dispenser packings are known to a large extent in varied configurations and for most different materials. Thus, most different flowable media are packaged in the cosmetics section, as cleansing agents, foodstuffs, in the construction industry and the like and are dispensed by means of suitable dispensing and proportioning devices. Particularly wide-spread are aerosol cans in which a propellant gas is admixed to a liquid medium under a pressure. The ejection of the medium is effected through an appropriate dispensing valve and a so-called spray head, in case of need. It is also known to accommodate the medium to be ejected in a pouch which is connected to the expulsion valve and is housed in a container which, in turn, is filled with a propellant medium. The propellant medium exerts a pressure onto all sides of the pouch and, thus, presses the medium out of the pouch if the expulsion valve is actuated. A packing of this type is used if the gaseous propellant needs to be prevented from contacting the medium to be ejected. In addition, this manner allows to eject pasty media by means of a gaseous propellant. It is also known to invert the assembly in the packing described last by filling the propellant into a pouch and filling the medium to be ejected in a container chamber which surrounds the pouch.
It is the object of the invention to provide a dispenser packing for a viscous or pasty material wherein a contact is also prevented between a gaseous propellant and the material to be ejected.
In the inventive packing, a piston which is slidingly movable in a cylindrical container divides the container into an upper chamber and a lower chamber. The upper chamber serves for receiving the material to be ejected and the lower chamber receives a hose-shaped or pouch-shaped expulsion element which bears on the piston and is filled with a propellant gas. Filling is effected via a charging valve disposed at the lower end of the container to the chest of which the expulsion element is connected. The upper end of the container has provided thereon a conventional expulsion valve which can be designed as a tilting valve in an aspect of the invention.
The expulsion valve may have been mounted already before the container is filled with the material to be dispensed. Therefore, it is unnecessary to feed the material under a pressure, if necessary, to the container through the charging valve. After filling it with the material to be dispensed, the piston is inserted and the expulsion element is mounted along with the charging valve. The latter is sealingly connected to the container in an efficient way which is known as such. Now, propellant gas is led into the expulsion element under a pressure through the charging valve up to a predetermined pressure with the feed volume and the pressure being sufficient to efficiently propel the piston up to the upper end of the container. It should be understood that the charging valve is disposed so as not to protrude beyond the lower end of the container and, hence, the container may be placed upright on a support. Besides, a cap, e.g. in plastic, can be slipped onto the lower end of the container to protect the charging valve and prevent any unintended actuation. This further will give the container a more sightly appearance. The expulsion element may be formed from a plastic sheeting which can be coated, in case of need, is spirally rolled, folded or is disposed in the shape of a concertina bellows in the lower chamber and is connected to the chest of the charging valve in an appropriate manner, e.g. by welding.
The container may be formed from sheet metal material or plastic. If sheet metal material is used a co-called valve plate, which is connected to the edge of the container by forming it thereto under a pressure, mostly is provided for both the expulsion valve and charging valve. However, if a plastic container is provided instead the charging valve, for example, may be joined or welded to the container edge in an appropriate manner. For the expulsion valve, a provision can also be made for the chest of the charging valve to be pressed into an aperture of the container. Particular molding operations will then be unnecessary. The valve chest may be made of an elastic material to enable it to be pressed into the container aperture. Subsequently, a dispensing stem with a valve member may be pressed into a passage of the chest.
The invention primarily serves for receiving viscous or pasty material such as sealing materials, which must not come into contact with air before being ejected because otherwise they will cure and/or react chemically. They further include foamed polyurethane or polyurethane adhesives for the construction sector, but also cosmetics, foodstuffs or the like.